RU56465U1 - WELL CLEANING DEVICE - Google Patents

Abstract

The proposal relates to the oil industry and can be used in the routine and overhaul of wells associated with flushing wells with absorbing formations from sand plugs, mud sediments, scale, etc.

A well cleaning device comprises a pipe string, a pipe plugged at the top, concentrically mounted in a hollow body, a self-sealing cuff with a clamping nut, an installation sleeve with a central channel. The installation sleeve is concentrically inserted into the hollow body on the outside of the nozzle, to which it is connected by bends connecting the inner space of the hollow body with the sand plug formation zone. The installation sleeve is made with the possibility of limited axial movement relative to the hollow body, which is additionally equipped with a saddle at the top inside, and short and long axial grooves connected from below by a radial groove from the bottom. The installation sleeve on top is rigidly connected to the hollow end, and from the bottom to the hollow tip, hermetically inserted into the hollow body with the possibility of axial and rotational movement. The hollow tip is equipped with a pin that is able to interact with the short, long axial and radial grooves of the hollow body. In the central channel of the installation sleeve above the nozzle there is a hollow cup with the possibility of limited axial movement and tight shutoff of the central channel when interacting with the upper part of the nozzle.

Inside the pipe in its lower part, a fluid flow swirl is rigidly mounted, made in the form of a flat screw twisting device, the screw surface of which is made with a variable pitch, decreasing in the axial direction of the fluid flow.

The hollow trailer is equipped with a valve that interacts with the saddle of the hollow body, with the location of the pin of the hollow tip in the upper part of the long axial groove - transport position. From above, the hollow trailer is movably connected to a sleeve rigidly connected to the pipe string and equipped with radial channels configured to overlap the hollow trailer when moving upward.

The proposed device for cleaning a well is reliable and efficient in operation, especially in wells having absorbing formations, due to cutting off the latter with subsequent tangential erosion of the sand plug by washing out the sandy sand mixture from the pipe string, which reduces the time for cleaning the well and saves money .

3 ill. for 1 liter

Description

The proposal relates to the oil industry and can be used in the routine and overhaul of wells associated with flushing wells with absorbing formations from sand plugs, mud sediments, scale, etc.

A device for washing sand plugs (Av. St. SU No. 857428, IPC 7 E 21 B 21/00, published in BI No. 31 of 08/23/1981), comprising a casing connected through a sleeve to a tubing string a pipe concentrically placed in it, forming an annular cavity with it.

The disadvantage of this device is that it does not prevent the absorption of washing liquid when cleaning the perforation holes of the filter from sand plugs. Therefore, as the plug is removed from the bottom and the filter is cleaned, the absorption rate of the washing liquid increases and the circulation and the removal of sand pulp to the surface cease. In this case, suspended particles of sand and dirt are deposited in the wellbore, which leads to severe emergency situations: pipe sticking, prolonged shutdown of wells for overhaul. The cessation of flushing due to absorption of the liquid leads to the fact that the well remains unpurified from the plug and is put into operation with a low flow rate, an increased content of mechanical impurities in the produced products, which leads to premature failure of the pumping equipment or standstill of the well due to the inability to remove cork flushing.

A device for washing sand plugs (Av. St. SU No. 1081334, IPC 7 E 21 B 21/00, published in BI No. 11 of 03/23/1984), comprising a casing connected through a sleeve to a tubing string a pipe concentrically placed in it, forming an annular cavity with it, two elastic cuffs installed in the upper and lower parts of the housing, and the coupling has radial channels for communicating the annular cavity formed by the housing and the pipe with the annulus.

The disadvantages of this device are:

firstly, during the descent of the device into the well, the cuffs are in constant contact with the walls of the well, resulting in friction, which leads to gradual wear of the cuffs during the descent of the device to the sand plug, especially in deep wells, which leads to a decrease in tightness in the process of flushing sand plugs and, as a result, to increasing the flow rate of flushing fluid in absorbing wells;

secondly, in paraffin wells during the descent, due to tight contact, the cuff may break, which reduces the efficiency of the device.

The closest in technical essence is a device for cleaning wells from sand plugs (patent RU No. 33600, IPC 7 E 21 B 30/00, 21/00, published in BI No. 30 dated 10.27.2003), containing a pipe concentrically mounted in a hollow body on which a self-sealing sleeve is installed, while it is provided with a hollow cylindrical nozzle connected to the lower part of the hollow body, provided with an installation sleeve on which the self-sealing sleeve is located, and a clamping nut mounted on the outer surface of the body, in addition, the hollow to the housing has the possibility of axial movement by a certain length relative to the installation sleeve, which allows you to create a limited load when pressing the self-sealing cuff to the walls of the well, equipped with a tip having longitudinal grooves on the outer surface and installed in the upper part of the body, equipped with four bends located radially in the hollow body and communicating the inner space of the bottom plugged with a sand plug formation zone.

The disadvantages of this device are:

- firstly, when unloading the device onto the sand plug, the traction can be bent or broken, and therefore the optimal distance for the effective erosion of the sand plug can be violated, and this reduces the reliability of the device;

- secondly, in the process of cleaning a well from a sand plug, the pressure of the flushing fluid above and below the self-sealing cuff is approximately equal to

as a result, in wells with low reservoir pressure, the washing fluid is absorbed by the layers, and therefore the erosion of sandy plugs to the surface stops, which reduces the efficiency of the device in such wells.

The technical task of the utility model is to increase the reliability and efficiency of the device in wells with absorbing formations having low reservoir pressure.

The stated technical problem is solved by a device for cleaning a well containing a pipe string, a hollow body, a plugged pipe, concentrically mounted in a hollow body, which is equipped with a self-sealing sleeve with a clamping nut, taps, an installation sleeve with a central channel, made with the possibility of limited axial movement relative to the hollow body .

What is new is that the pipe is plugged at the top, and a fluid flow swirl is installed rigidly in the bottom, made in the form of a flat screw screw device, the screw surface of which is made with a variable pitch, decreasing in the axial direction of the fluid flow, while the hollow body is additionally equipped with a top inside the saddle and the bottom with short and long axial grooves connected from below by a radial groove, and the installation sleeve is concentrically inserted into the hollow body outside the nozzle with which it is connected bends that communicate the inner space of the hollow body with the zone of formation of the sand plug, while the installation sleeve is rigidly connected from above to the hollow end, and from below to the hollow tip, hermetically inserted into the hollow body with the possibility of axial and rotational movement, and equipped with a pin, which is made with the possibility of interaction with the grooves of the hollow body, moreover, in the central channel of the installation sleeve above the nozzle there is a hollow glass with the possibility of limited axial movement and seal overlapping the central channel of the installation sleeve when interacting with the upper part of the pipe, while the hollow end is equipped with a valve that interacts with the seat of the hollow body when the pin of the hollow tip is located in the upper part of the long radial groove - transport position, and on top of the hollow end is movably connected to the sleeve, rigidly connected to the pipe string and equipped with radial

channels made with the possibility of overlapping the hollow trailer when moving up.

The figure 1 shows the proposed device in longitudinal section in the working position.

The figure 2 shows a section aa of the proposed device.

The figure 3 shows a scan of grooves made on a hollow body.

The device for cleaning a well contains a pipe string 1 (see FIG. 1), a pipe plugged at the top, concentrically mounted in a hollow body 3, a self-sealing sleeve 4 with a clamping nut 5, an installation sleeve 6 with a central channel 7. Installation sleeve 6 (see figure 2) is concentrically inserted into the hollow body 3 on the outside of the pipe 2, to which it is connected by taps 8 connecting the inner space 9 of the hollow body 3 with the formation zone of the sand plug (not shown in Figs. 1, 2, 3). The installation sleeve 6 is made with limited axial movement relative to the hollow body 3.

The hollow body 3 is additionally equipped with a saddle 10 at the top inside, and a short 11 (see FIG. 3) and a long 12 axial grooves connected from below by a radial groove 13 from the bottom.

The installation sleeve 7 (see Fig. 1) is rigidly connected from above to the hollow end 14, and from the bottom to the hollow tip 15, hermetically inserted into the hollow body 3 with the possibility of axial and rotational movement. The hollow tip 15 is equipped with a pin 16, which has the ability to interact with a short 11 (see figure 3), a long 12 axial and radial 13 grooves of the hollow body 3.

In the central channel 7 (see Fig. 1) of the mounting sleeve 6 above the pipe 2 there is a hollow glass 17 with the possibility of limited axial movement and tight shutoff of the central channel 7 when interacting with the upper part of the pipe 2. Inside the pipe 2 in its lower part there is a swirl 18 fluid flow, made in the form of a flat screw twisting device, the screw surface of which is made with a variable pitch, decreasing in the axial direction of the fluid flow

The hollow trailer 15 is equipped with a valve 19, interacting with the seat 10 of the hollow body 3, when the pin 16 of the hollow tip 15 is located in the upper part of the long

axial groove 12 - transport position. On top of the hollow end 14 is movably connected to the sleeve 20, rigidly connected to the pipe string 1, and equipped with radial channels 21 made with the possibility of overlapping the hollow end 15 when moving up.

The device operates as follows.

The device is installed in the transport position, that is, the pin 16 (see FIG. 3) of the hollow tip 15 is located in the upper part of the long axial groove 12, while the valve 19 is closed, that is, sealed on the seat 10.

After that, the complete device (see Fig. 1) on the pipe string 1 (for example, the tubing string) is lowered into the well until the lower end (for example, made in the form of a toothed crown) of the hollow body 3 interacts with the sand plug to be cleaned, while control is carried out by the weight indicator installed on the wellhead.

After the interaction of the lower end of the hollow body 3 with the sand plug, the device is unloaded to the sand plug, with the hollow end 14 being sealed with the upper end hermetically seals the radial channels 21 of the sleeve 20, and then the pin 16 is moved to the reamer length (see FIG. 3) of a long axial groove 12, after which a weight drop is observed on the weight indicator. The hollow body 3 bottom end is fixed from turning in a sand cork.

Next, the device is turned counterclockwise by the length of the scan of the radial groove 13. As a result of the operation, the pin 16 moves along the radial groove 13 to the lower part of the short axial groove 11, while all the parts of the device except the hollow body 3 (see Fig. 1), fixed by its lower end in a sand plug and rigidly connected from above to the hollow body 3 of the seat 10, the self-sealing cuff 4 with the clamping nut 5 remaining stationary rotate counterclockwise to the length of the radial groove 1 3. Unloading of the device to the sand plug continues, while the pin 16 can only move along a short axial groove 11 (see figure 3), which allows the valve 19 to be fixed (see figure 1) in the open position, that is, an annular gap is formed (not shown in FIGS. 1, 2, 3) between the seat 10 and the valve 18.

Next, the erosion of sand cork begins. For this, the flushing fluid is pumped into the annular space of the well (not shown in FIGS. 1, 2, 3).

The flow of flushing fluid through the annulus of the borehole reaches the self-sealing collar 4, which is hermetically pressed against the walls of the borehole, after which it enters the seat 10 and then through the annular gap formed between the seat 10 and valve 19 into the inner space of the hollow body 3, from where through taps 8 (see figure 2) enters the nozzle 2. Next, the flow of washing liquid descends down the nozzle 2 (see figure 1) and enters the swirl 5, made in the form of a flat screw screw device, a screw ited which is provided with a variable pitch which decreases in the axial direction of fluid flow, which reduces the hydraulic losses arising from eddy formation and flow separation on the screw surface. The flow of flushing fluid enters the swirl 5 with a degree of swirl close to zero, and gradually swirls in the inter-screw channel 23. Then the tangentially swirling flow of flushing fluid acts on the sand plug, eroding it. The pressure drop above and below the self-sealing collar 4 additionally compresses the latter to the walls of the well, hermetically separating the annulus of the well.

Further, the sand plug in the form of a water-sand mixture washed out by the fluid flow rises from the zone of formation of the sand plug and, through the annular space 22 formed by the pipe 2 and the hollow tip 15, acts from below on the end face of the hollow glass 17, raising the latter. The hollow glass 17 moves upward, forming an annular gap (not shown in FIGS. 1, 2, 3) between the pipe 2 which is muffled from above and the hollow glass 17. As a result, the washed sandy water mixture rushes into the central channel 7 of the installation sleeve 6 and then along the hollow end 14 enters the pipe string 1, where it rises up, since the radial channels 21 of the sleeve 20 are hermetically closed by the upper end of the hollow end 14.

As the sand plug is eroded, the pipe string 1 is lowered downward, and if necessary (depending on the height of the sand plug) they increase, while the pumping of the flushing fluid into the annular space of the well continues. Sand cork erosion continues until visually reduced flow

washed out of the well water-sand mixture or circulation will not stop. This means that the sand plug is washed out to the formation (not shown in FIGS. 1, 2, 3), which began to absorb the flushing fluid and therefore the fluid flow in the device no longer ensures that the sandy mixture in the pipe string 1 will rise to the surface.

At the same time, the hollow glass 17 returns to its original position, since the flow of the washed-out sandy-sand mixture ceases to affect its lower end and it seals under its own weight on the nozzle 2, which is muffled from above, and prevents the spreading of the washed-out sandy-sand mixture back into the sand cork zone.

To remove the water-sand mixture inside the pipe string 1 above the sleeve 20, the pipe string 1 is lifted from the wellhead by about 2-3 meters, while the upper end of the hollow end 14 first goes out of contact with the sleeve 20, as a result of which its radial channels open 21, and then the pin 16 moves to the upper part of the short axial groove 11 until it abuts against the upper end of the latter.

By supplying flushing fluid to the annulus of the well and then, since the self-sealing collar 4 is pressed against the walls of the well through radial channels 21 of the sleeve 20, the sandy mixture located in the pipe string 1 is washed to the surface. The water-sand mixture washed to the surface is sent to a gutter or barn.

To continue cleaning the well from the sand plug, the pipe string 1 is lowered down until the device is unloaded onto the sand plug, after which the whole cycle of work described above is repeated. At the end of the well cleaning from the sand plug, the device is removed from the well.

The proposed device for cleaning a well is reliable and efficient in operation, especially in wells having absorbing formations, due to cutting off the latter with subsequent tangential erosion of the sand plug by washing out the sandy sand mixture from the pipe string, which reduces the time for cleaning the well and saves money .

Claims (1)

A device for cleaning a well, comprising a pipe string, a hollow body, a plugged pipe, concentrically mounted in a hollow body, which is equipped with a self-sealing sleeve with a clamping nut and a cylindrical nozzle mounted on the lower end of the hollow body, taps connecting the inner space of the pipe with the sand plug formation zone , limiter and installation sleeve with a central channel, made with the possibility of limited axial movement relative to the hollow body, characterized in that the side is muffled from above, and from below, a fluid flow swirl is rigidly mounted, made in the form of a flat screw twisting device, the screw surface of which is made with a variable pitch, decreasing in the axial direction of the fluid flow, while the hollow body is additionally equipped with a saddle and a short long axial grooves connected from below by a radial groove, and the installation sleeve is concentrically inserted into the hollow body outside the nozzle, to which it is connected by bends that communicate the internal space of the hollow body with the zone of formation of the sand plug, while the installation sleeve is rigidly connected to the hollow end from the top, and from the bottom to the hollow tip, hermetically inserted into the hollow body with the possibility of axial and rotational movement, and equipped with a pin that is designed to interact with grooves hollow body, moreover, in the central channel of the installation sleeve above the nozzle there is a hollow glass with the possibility of limited axial movement and hermetically sealed central the channel of the installation sleeve when interacting with the upper part of the nozzle, while the hollow end is equipped with a valve that interacts with the seat of the hollow body when the pin of the hollow tip is located in the upper part of the long radial groove - transport position, and on top of the hollow end is movably connected to the sleeve rigidly connected to a column of pipes and equipped with radial channels, made with the possibility of overlapping a hollow trailer when moving up.